The meat-packing industry has been the scene of important advances in the area of automated loading and packaging of specially prepared meat items such as weiners, frankfurters, and so forth. These advances, however, have been limited to the area of cooked meat products, including cooked sausages, weiners and the like. No similar automation advances have been developed for the handling and packaging of uncooked sausages. As a result, it is the almost universal practice to hand-load the uncooked sausages into trays. The reason for this failure on the part of the industry to automate and thus render more efficient the handling and packaging of uncooked sausage, as compared to any similar but cooked item like a cooked sausage, cooked weiner, and so forth. Uncooked sausages are extremely flaccid, limp and "squishy", to such an extent that machine components like tongs or suction devices are not able to handle them consistently and with a failure rate near zero. It will be understood that it is quite essential for any automated machine to be capable of continuous operation with a virtually zero failure rate, since a single failure can cause the machine to be shut down, result in expensive "down time", and so forth.
To use a specific example, it takes five workers about one hour to load 1,000 pounds of uncooked sausage into trays ready for wrapping. This represents several thousand individual sausages. If an automated machine were to take the place of these five workers, and run continuously over an eight-hour shift without a single failure on a single sausage (i.e., without allowing a single sausage to become stuck in the machine, gum up the operation of the machine, and the like), the failure rate would have to be less than one sausage in better than ten-thousand sausages, this being less than 1/100th of 1%. Until now, due to the flaccidity of uncooked sausages, this kind of performance simply has not been achievable.
Accordingly, it is a primary aspect of this invention and of parent U.S. Pat. No. 4,173,107, to succeed, where prior attempts have failed, in providing an automated machine capable of packaging uncooked sausages into sausage trays and also capable of rejecting any sausages having a length either greater or smaller than a specific range suitable for the particular tray size, thus effecting weight control in the packed trays.
This invention provides a reciprocating mechanism for repeatedly pushing items stacked on a support surface, the mechanism comprising: a low friction support table; a pusher member; reciprocating power means for urging the pusher member alternatingly in a forward direction across the support surface and then in a rearward direction; means laterally of the pusher member defining at least one cam track having a lower track segment substantially parallel with the support surface, an upward segment at the forward end of the lower segment, a return segment above said lower segment, and a downward segment joining the return and lower segments at the rear; follower means on the pusher member for following said cam track; and spring means for gradually increasing upward force on the pusher member as the latter moves forwardly, the upward force at the forward end being strong enough to raise the pusher member up to the return leg, but being weak enough at the rearward end to allow the pusher member to return by its own weight to the lower leg.
In yet another aspect, this invention provides an apparatus for using pressurized gas such as air for handling soft, flaccid, easily deformable, uncooked sausages without unduly damaging them, comprising: a member positioned on one side and slightly above the support table, having a cavity with a plurality of holes oriented to create a directed curtain of air across the top of the table when the cavity is air pressurized. This pressurized air causes positive placement of the sausages on the support table without unacceptably deforming the sausages.